1. Field of the Invention
The present invention relates to a control technique for job execution in a computer system which can co-execute a plurality of processing functions, and more particularly to a distributed control method and apparatus for job execution to distribute the processing of job control statements or the processing to secure or release resources into a plurality of discrete processes and to accomplish them in parallel.
2. Description of Related Art
According to the related art, in distributed control of job execution in a computer system able to execute a plurality of processes, a plurality of jobs are simultaneously executed in parallel in discrete processes, and no consideration is given to the distribution of the steps of processing at the start and end of each program within one job.
The processing time of a job includes not only the total sum of the periods taken by the execution of programs at different steps stated within a job but also those taken by the steps of processing at the start and end of each program. Thus, at the start of each program, analysis and execution of a plurality of job control statements are required, and at the same time processing to secure resources schedule for use by the program is also needed. Furthermore, at the time of ending each program, processing to release the resources used by the program is also required.
The techniques for executing the processing to secure resources at the time of starting a program consecutively in a single process are disclosed in "ACOS-4/XVP Job Management Reference Manual", DDA81E-2, NEC Corporation, 1992, pp. 3-15 to 3-22.
In this related art, there is the problem that the total processing time for securing resources at the time of starting a program will increase in proportion to the total number of the resources secured. Moreover, until the processing to secure a resource currently under way is completed, securing the next resource, even though available, cannot be processed, and accordingly a long time is required to secure all the needed resources. The same is true of the release of resources. Furthermore, though some job control statements, typically file management statements, permit parallel processing, analysis and execution of job control statements, as long as accomplished in a single process, have to be processed consecutively and the time taken to execute each single job is not reduced.